From c15e1bdda4365a5f17cdadf22bf1c1df13884a9e Mon Sep 17 00:00:00 2001 From: Heikki Krogerus Date: Fri, 21 Aug 2020 13:53:42 +0300 Subject: device property: Fix the secondary firmware node handling in set_primary_fwnode() When the primary firmware node pointer is removed from a device (set to NULL) the secondary firmware node pointer, when it exists, is made the primary node for the device. However, the secondary firmware node pointer of the original primary firmware node is never cleared (set to NULL). To avoid situation where the secondary firmware node pointer is pointing to a non-existing object, clearing it properly when the primary node is removed from a device in set_primary_fwnode(). Fixes: 97badf873ab6 ("device property: Make it possible to use secondary firmware nodes") Cc: All applicable Signed-off-by: Heikki Krogerus Signed-off-by: Rafael J. Wysocki --- drivers/base/core.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) (limited to 'drivers/base/core.c') diff --git a/drivers/base/core.c b/drivers/base/core.c index ac1046a382bc..f6f620aa9408 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -4264,9 +4264,9 @@ static inline bool fwnode_is_primary(struct fwnode_handle *fwnode) */ void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode) { - if (fwnode) { - struct fwnode_handle *fn = dev->fwnode; + struct fwnode_handle *fn = dev->fwnode; + if (fwnode) { if (fwnode_is_primary(fn)) fn = fn->secondary; @@ -4276,8 +4276,12 @@ void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode) } dev->fwnode = fwnode; } else { - dev->fwnode = fwnode_is_primary(dev->fwnode) ? - dev->fwnode->secondary : NULL; + if (fwnode_is_primary(fn)) { + dev->fwnode = fn->secondary; + fn->secondary = NULL; + } else { + dev->fwnode = NULL; + } } } EXPORT_SYMBOL_GPL(set_primary_fwnode); -- cgit From 693a8e936590f93451e6f5a3d748616f5a59c80b Mon Sep 17 00:00:00 2001 From: Michał Mirosław Date: Fri, 28 Aug 2020 18:14:35 +0200 Subject: driver code: print symbolic error code MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit dev_err_probe() prepends the message with an error code. Let's make it more readable by translating the code to a more recognisable symbol. Fixes: a787e5400a1c ("driver core: add device probe log helper") Signed-off-by: Michał Mirosław Link: https://lore.kernel.org/r/ea3f973e4708919573026fdce52c264db147626d.1598630856.git.mirq-linux@rere.qmqm.pl Signed-off-by: Greg Kroah-Hartman --- drivers/base/core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/base/core.c') diff --git a/drivers/base/core.c b/drivers/base/core.c index ac1046a382bc..1a4706310b28 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -4237,10 +4237,10 @@ int dev_err_probe(const struct device *dev, int err, const char *fmt, ...) vaf.va = &args; if (err != -EPROBE_DEFER) { - dev_err(dev, "error %d: %pV", err, &vaf); + dev_err(dev, "error %pe: %pV", ERR_PTR(err), &vaf); } else { device_set_deferred_probe_reason(dev, &vaf); - dev_dbg(dev, "error %d: %pV", err, &vaf); + dev_dbg(dev, "error %pe: %pV", ERR_PTR(err), &vaf); } va_end(args); -- cgit From 6b57b15abe11aa334ebf726e02c0deaf123ba040 Mon Sep 17 00:00:00 2001 From: Saravana Kannan Date: Tue, 1 Sep 2020 11:44:44 -0700 Subject: driver core: Fix device_pm_lock() locking for device links This commit fixes two issues: 1. The lockdep warning reported by Dong Aisheng [1]. It is a warning about a cycle (dpm_list_mtx --> kn->active#3 --> fw_lock) that was introduced when device-link devices were added to expose device link information in sysfs. The patch that "introduced" this cycle can't be reverted because it's fixes a real SRCU issue and also ensures that the device-link device is deleted as soon as the device-link is deleted. This is important to avoid sysfs name collisions if the device-link is create again immediately (this can happen a lot with deferred probing). 2. Inconsistency in grabbing device_pm_lock() during device link deletion Some device link deletion code paths grab device_pm_lock(), while others don't. The device_pm_lock() is grabbed during device_link_add() because it checks if the supplier is in the dpm_list and also reorders the dpm_list. However, when a device link is deleted, it does not do either of those and therefore device_pm_lock() is not necessary. Dropping the device_pm_lock() in all the device link deletion paths removes the inconsistency in locking. Thanks to Stephen Boyd for helping me understand the lockdep splat. Fixes: 843e600b8a2b ("driver core: Fix sleeping in invalid context during device link deletion") [1] - https://lore.kernel.org/lkml/CAA+hA=S4eAreb7vo69LAXSk2t5=DEKNxHaiY1wSpk4xTp9urLg@mail.gmail.com/ Reported-by: Dong Aisheng Signed-off-by: Saravana Kannan Tested-by: Peng Fan Link: https://lore.kernel.org/r/20200901184445.1736658-1-saravanak@google.com Signed-off-by: Greg Kroah-Hartman --- drivers/base/core.c | 4 ---- 1 file changed, 4 deletions(-) (limited to 'drivers/base/core.c') diff --git a/drivers/base/core.c b/drivers/base/core.c index 1a4706310b28..97812a5f42b8 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -807,9 +807,7 @@ static void device_link_put_kref(struct device_link *link) void device_link_del(struct device_link *link) { device_links_write_lock(); - device_pm_lock(); device_link_put_kref(link); - device_pm_unlock(); device_links_write_unlock(); } EXPORT_SYMBOL_GPL(device_link_del); @@ -830,7 +828,6 @@ void device_link_remove(void *consumer, struct device *supplier) return; device_links_write_lock(); - device_pm_lock(); list_for_each_entry(link, &supplier->links.consumers, s_node) { if (link->consumer == consumer) { @@ -839,7 +836,6 @@ void device_link_remove(void *consumer, struct device *supplier) } } - device_pm_unlock(); device_links_write_unlock(); } EXPORT_SYMBOL_GPL(device_link_remove); -- cgit